:root {
  --color-bg: #15130F;
  --color-panel: #1C1913;
  --color-panel-raised: #242017;
  --color-border: #3A3325;
  --color-border-strong: #4E4430;
  --color-accent: #F2761B;
  --color-accent-dark: #C2560E;
  --color-accent-glow: rgba(242, 118, 27, 0.42);
  --color-accent-soft: rgba(242, 118, 27, 0.10);
  --color-accent-faint: rgba(242, 118, 27, 0.16);
  --color-text: #F2EDE2;
  --color-text-muted: #A89D8A;
  --color-success: #4CC38A;
  --color-warn: #E0B24E;
  --color-error: #E2503A;
  --color-white: #FFFFFF;
  --color-black: #000000;
  --color-black-shadow: rgba(0, 0, 0, 0.38);
  --color-on-accent: #1A0F04;
  --color-overlay: rgba(21, 19, 15, 0.82);
  --color-overlay-strong: rgba(21, 19, 15, 0.96);
  --color-focus-shadow: rgba(242, 118, 27, 0.24);
  --color-table-stripe: rgba(242, 118, 27, 0.035);
  --font-display: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-body: 'Inter', 'Noto Sans SC', -apple-system, 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, 'Liberation Mono', monospace;
  --radius-small: 8px;
  --radius-control: 12px;
  --radius-card: 20px;
  --radius-large: 28px;
  --radius-pill: 999px;
  --shadow-card: 0 18px 44px var(--color-black-shadow);
  --shadow-accent: 0 6px 26px var(--color-accent-glow);
  --shadow-focus: 0 0 0 4px var(--color-focus-shadow);
  --content-wide: 1352px;
  --content-reading: 820px;
  --header-height: 66px;
  --gutter: 44px;
  --section-space: 96px;
  --transition-fast: 180ms ease;
  --transition-base: 260ms ease;
  --sticky-offset: 82px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  min-width: 320px;
  font-size: 16px;
  scroll-behavior: smooth;
  scroll-padding-top: var(--sticky-offset);
  background: var(--color-bg);
}

html.nav-open {
  overflow: hidden;
}

body {
  min-width: 320px;
  margin: 0;
  overflow-x: clip;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

::selection {
  background: var(--color-accent-dark);
  color: var(--color-text);
}

img,
svg,
video {
  display: block;
  max-width: 100%;
}

img {
  height: auto;
}

button,
input,
select,
textarea {
  color: inherit;
  font: inherit;
}

button {
  border: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

p,
ul,
ol,
blockquote,
pre,
table {
  margin-top: 0;
}

p:last-child,
ul:last-child,
ol:last-child,
blockquote:last-child {
  margin-bottom: 0;
}

ul,
ol {
  padding-left: 1.3rem;
}

li + li {
  margin-top: 0.4rem;
}

code,
kbd,
samp {
  font-family: var(--font-mono);
}

:not(pre) > code {
  overflow-wrap: anywhere;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-small);
  background: var(--color-panel-raised);
  color: var(--color-text);
  padding: 0.12em 0.38em;
  font-size: 0.88em;
}

pre {
  max-width: 100%;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-panel);
  padding: 1rem;
  -webkit-overflow-scrolling: touch;
}

pre code {
  white-space: pre;
}

hr {
  height: 1px;
  margin: 2rem 0;
  border: 0;
  background: var(--color-border);
}

h1,
h2,
h3,
h4 {
  margin-top: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  line-height: 1.18;
  text-wrap: balance;
}

h1,
h2,
h3 {
  display: block;
}

h1 {
  margin-bottom: 1.4rem;
  font-size: clamp(3.25rem, 5.2vw, 4.5rem);
  font-weight: 900;
  letter-spacing: -0.015em;
}

h2 {
  margin-bottom: 1.2rem;
  font-size: clamp(2rem, 3.4vw, 3.25rem);
  font-weight: 900;
  letter-spacing: -0.01em;
}

h3 {
  margin-bottom: 0.8rem;
  font-size: clamp(1.25rem, 2vw, 1.65rem);
  font-weight: 800;
}

h4 {
  margin-bottom: 0.65rem;
  font-size: 1rem;
  font-weight: 800;
}

a:focus-visible,
button:focus-visible,
summary:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible,
[role="tab"]:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-small);
}

.wrap {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.reading-wrap {
  width: 100%;
  max-width: var(--content-reading);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.section {
  padding-top: var(--section-space);
  padding-bottom: var(--section-space);
}

.section-compact {
  padding-top: calc(var(--section-space) * 0.62);
  padding-bottom: calc(var(--section-space) * 0.62);
}

.min-zero,
.grid > *,
.flex > * {
  min-width: 0;
}

.no-break {
  white-space: nowrap;
}

.mono {
  font-family: var(--font-mono);
}

.muted {
  color: var(--color-text-muted);
}

.accent-text {
  color: var(--color-accent);
}

.gradient-text {
  background: linear-gradient(100deg, var(--color-warn), var(--color-accent), var(--color-accent-dark));
  color: transparent;
  filter: drop-shadow(0 0 22px var(--color-accent-glow));
  background-clip: text;
  -webkit-background-clip: text;
}

.eyebrow {
  margin-bottom: 0.8rem;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.section-intro {
  max-width: 62ch;
  color: var(--color-text-muted);
  font-size: clamp(1rem, 1.5vw, 1.15rem);
}

.badge,
.fact-pill,
.tag {
  display: inline-flex;
  min-height: 28px;
  max-width: 100%;
  align-items: center;
  gap: 0.5rem;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  background: var(--color-panel);
  color: var(--color-text-muted);
  padding: 0.3rem 0.78rem;
  font-size: 0.78rem;
  line-height: 1.3;
}

.badge-dot {
  width: 7px;
  height: 7px;
  flex: 0 0 auto;
  border-radius: var(--radius-pill);
  background: var(--color-accent);
  box-shadow: 0 0 8px var(--color-accent-glow);
}

.tag {
  color: var(--color-accent);
  font-family: var(--font-mono);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.85rem;
}

.btn {
  display: inline-flex;
  min-width: 24px;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  gap: 0.55rem;
  border: 1px solid transparent;
  border-radius: var(--radius-pill);
  padding: 0.76rem 1.55rem;
  font-family: var(--font-display);
  font-weight: 800;
  line-height: 1.1;
  cursor: pointer;
  transition: transform var(--transition-fast), border-color var(--transition-fast), background var(--transition-fast), box-shadow var(--transition-fast), color var(--transition-fast);
}

.btn:hover {
  transform: translateY(-2px);
}

.btn-primary {
  background: var(--color-accent);
  color: var(--color-on-accent);
  box-shadow: var(--shadow-accent);
}

.btn-primary:hover {
  box-shadow: 0 10px 32px var(--color-accent-glow);
}

.btn-secondary {
  border-color: var(--color-border-strong);
  background: var(--color-panel);
  color: var(--color-text);
}

.btn-secondary:hover {
  border-color: var(--color-accent);
  background: var(--color-accent-soft);
}

.btn-quiet {
  border-color: var(--color-border);
  background: transparent;
  color: var(--color-text-muted);
}

.btn-quiet:hover {
  border-color: var(--color-border-strong);
  color: var(--color-text);
}

.btn-disabled,
.btn:disabled {
  border-color: var(--color-border);
  background: var(--color-panel);
  color: var(--color-text-muted);
  box-shadow: none;
  cursor: not-allowed;
  opacity: 0.62;
  transform: none;
}

.panel,
.card {
  min-width: 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-card);
  background: var(--color-panel);
  box-shadow: var(--shadow-card);
}

.panel-raised {
  background: var(--color-panel-raised);
}

.card {
  padding: 1.5rem;
  transition: transform var(--transition-base), border-color var(--transition-base), box-shadow var(--transition-base);
}

.card:hover {
  border-color: var(--color-border-strong);
  transform: translateY(-3px);
}

.card[data-tilt] {
  transform-style: preserve-3d;
  will-change: transform;
}

.icon-disc {
  display: inline-flex;
  width: 42px;
  height: 42px;
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-panel-raised);
  color: var(--color-accent);
}

.icon-disc svg {
  width: 22px;
  height: 22px;
}

.site-head {
  position: relative;
  z-index: 80;
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
}

.site-head-inner {
  display: flex;
  min-height: var(--header-height);
  align-items: center;
  gap: 2rem;
}

.site-brand {
  display: inline-flex;
  min-width: max-content;
  min-height: 44px;
  align-items: center;
  gap: 0.65rem;
}

.site-brand img {
  width: 30px;
  height: 30px;
  flex: 0 0 auto;
}

.site-brand-name {
  font-family: var(--font-display);
  font-size: 1.18rem;
  font-weight: 800;
  letter-spacing: 0.02em;
}

.site-brand-local {
  color: var(--color-text-muted);
  font-size: 0.88rem;
  font-weight: 500;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 1.65rem;
  margin-left: 0.9rem;
}

.desktop-nav a {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.desktop-nav a:hover,
.desktop-nav a.is-active {
  color: var(--color-text);
}

.desktop-nav a.is-active {
  font-weight: 700;
}

.header-tools {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-left: auto;
}

.login-link {
  display: inline-flex;
  min-height: 40px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-pill);
  padding: 0.45rem 1.25rem;
  color: var(--color-text);
  font-size: 0.88rem;
  font-weight: 700;
  transition: border-color var(--transition-fast), background var(--transition-fast);
}

.login-link:hover {
  border-color: var(--color-accent);
  background: var(--color-accent-soft);
}

.language-menu {
  position: relative;
}

.language-toggle {
  display: inline-flex;
  min-width: 44px;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  gap: 0.35rem;
  border-radius: var(--radius-control);
  background: transparent;
  color: var(--color-text-muted);
  cursor: pointer;
}

.language-popover {
  position: absolute;
  top: calc(100% + 0.5rem);
  right: 0;
  z-index: 95;
  display: none;
  width: 170px;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-panel-raised);
  box-shadow: var(--shadow-card);
  padding: 0.4rem;
}

.language-menu.is-open .language-popover {
  display: block;
}

.language-popover a {
  display: flex;
  min-height: 40px;
  align-items: center;
  border-radius: var(--radius-small);
  padding: 0.45rem 0.7rem;
  color: var(--color-text-muted);
}

.language-popover a:hover,
.language-popover a[aria-current="true"] {
  background: var(--color-accent-soft);
  color: var(--color-text);
}

.menu-toggle {
  display: none;
  width: 44px;
  min-width: 44px;
  height: 44px;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-control);
  background: var(--color-panel);
  color: var(--color-text);
  cursor: pointer;
}

.menu-toggle-lines,
.menu-toggle-lines::before,
.menu-toggle-lines::after {
  width: 18px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: currentColor;
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.menu-toggle-lines {
  position: relative;
}

.menu-toggle-lines::before,
.menu-toggle-lines::after {
  position: absolute;
  left: 0;
  content: "";
}

.menu-toggle-lines::before {
  transform: translateY(-6px);
}

.menu-toggle-lines::after {
  transform: translateY(6px);
}

.menu-toggle[aria-expanded="true"] .menu-toggle-lines {
  background: transparent;
}

.menu-toggle[aria-expanded="true"] .menu-toggle-lines::before {
  transform: rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .menu-toggle-lines::after {
  transform: rotate(-45deg);
}

.mobile-nav {
  position: absolute;
  top: 100%;
  right: 0;
  left: 0;
  z-index: 92;
  display: none;
  max-height: calc(100dvh - var(--header-height));
  overflow-y: auto;
  overscroll-behavior: contain;
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-panel-raised);
  padding: 0.7rem var(--gutter) 1rem;
}

.mobile-nav.is-open {
  display: block;
}

.mobile-nav a {
  display: flex;
  width: 100%;
  min-height: 46px;
  align-items: center;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  padding: 0.7rem 0.25rem;
}

.mobile-nav a.is-active {
  color: var(--color-accent);
  font-weight: 700;
}

.mobile-languages {
  display: grid;
  gap: 0.15rem;
  margin-top: 0.7rem;
}

.mobile-languages strong {
  padding: 0.55rem 0.25rem;
  color: var(--color-text);
  font-size: 0.8rem;
}

.nav-veil {
  position: fixed;
  inset: var(--header-height) 0 0;
  z-index: 70;
  display: none;
  background: var(--color-overlay);
}

.nav-veil.is-open {
  display: block;
}

.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-panel);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.35fr 1fr 1fr 0.8fr;
  gap: 2.5rem;
  padding-top: 64px;
  padding-bottom: 48px;
}

.footer-brand {
  max-width: 34ch;
}

.footer-brand .site-brand {
  margin-bottom: 1rem;
}

.footer-brand p,
.footer-column a,
.footer-languages a {
  color: var(--color-text-muted);
}

.footer-column h2 {
  margin-bottom: 1rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.footer-links,
.footer-languages {
  display: grid;
  gap: 0.28rem;
}

.footer-links a,
.footer-languages a {
  display: inline-flex;
  min-height: 32px;
  align-items: center;
  width: fit-content;
}

.footer-links a:hover,
.footer-languages a:hover {
  color: var(--color-text);
}

.footer-bottom {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  border-top: 1px solid var(--color-border);
  padding-top: 1.3rem;
  padding-bottom: 1.6rem;
  color: var(--color-text-muted);
  font-size: 0.82rem;
}

.footer-legal {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-legal a {
  min-height: 24px;
}

.reveal {
  transition: opacity 620ms ease, transform 620ms ease;
}

.reveal.pending {
  opacity: 0;
  transform: translateY(16px);
}

.reveal.shown {
  opacity: 1;
  transform: none;
}

.prose {
  color: var(--color-text-muted);
}

.prose h2,
.prose h3,
.prose h4,
.prose strong {
  color: var(--color-text);
}

.prose h2 {
  margin-top: 3.5rem;
}

.prose h3 {
  margin-top: 2.2rem;
}

.prose a {
  color: var(--color-accent);
  text-decoration: underline;
  text-decoration-color: var(--color-accent-dark);
  text-underline-offset: 0.18em;
}

.prose a.btn-primary {
  color: var(--color-on-accent);
  text-decoration: none;
}

.prose blockquote {
  margin-inline: 0;
}

.prose img {
  border-radius: var(--radius-control);
}

.prose > .data-table {
  display: block;
  min-width: 0;
  max-width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

[data-draw-line] {
  vector-effect: non-scaling-stroke;
}

@media (max-width: 1120px) {
  :root {
    --gutter: 28px;
  }

  .desktop-nav {
    gap: 1rem;
  }

  .footer-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 900px) {
  .desktop-nav,
  .language-menu {
    display: none;
  }

  .menu-toggle {
    display: inline-flex;
  }

  .header-tools {
    margin-left: auto;
  }
}

@media (max-width: 768px) {
  :root {
    --gutter: 20px;
    --section-space: 72px;
  }

  h1 {
    font-size: clamp(1.75rem, 9vw, 2.5rem);
    line-height: 1.12;
    letter-spacing: -0.015em;
  }

  h2 {
    font-size: clamp(1.65rem, 7vw, 2.2rem);
  }

  .footer-grid {
    grid-template-columns: 1fr;
  }

  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 640px) {
  :root {
    --gutter: 16px;
  }

  body,
  main,
  section,
  article,
  .wrap,
  .reading-wrap {
    max-width: 100%;
  }

  .site-head-inner {
    gap: 0.55rem;
  }

  .site-brand-local {
    display: none;
  }

  .login-link {
    min-height: 38px;
    padding-inline: 0.9rem;
  }

  .button-row {
    align-items: stretch;
  }

  .button-row .btn {
    flex: 1 1 auto;
  }

  .card[data-tilt],
  .tilt,
  .tilted {
    transform: none;
  }

  .decor,
  .atmosphere,
  [data-decorative] {
    max-width: 100%;
  }
}

@media (max-width: 390px) {
  .site-brand-name {
    font-size: 1rem;
  }

  .header-tools {
    gap: 0.35rem;
  }

  .login-link {
    padding-inline: 0.75rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-duration: 0s;
  }

  .reveal,
  .reveal.pending,
  .reveal.shown {
    opacity: 1;
    transform: none;
    transition: none;
  }

  .card,
  .btn {
    transition: none;
  }

  .card:hover,
  .btn:hover {
    transform: none;
  }
}